std::chrono::operator<<(std::chrono::hh_mm_ss)
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                    |   Defined in header  <chrono>
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|   template< class CharT, class Traits, class Duration > std::basic_ostream<CharT, Traits>&  | 
(since C++20) | |
Outputs t into the stream os.
Equivalent to return os << std::format(os.getloc(), STATICALLY_WIDEN<CharT>("{:L%T}"), hms); where STATICALLY_WIDEN<CharT>("{:L%T}") is "{:L%T}" if CharT is char, and L"{:L%T}" if CharT is wchar_t.
Parameters
| os | - | the output stream | 
| t | - | the time of day to be output | 
Return value
os
Example
| This section is incomplete Reason: no example  | 
Defect reports
The following behavior-changing defect reports were applied retroactively to previously published C++ standards.
| DR | Applied to | Behavior as published | Correct behavior | 
|---|---|---|---|
| P2372R3 | C++20 | the given locale was used by default | L is needed to use the given locale
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See also
|    (C++20)  | 
  stores formatted representation of the arguments in a new string  (function template)  | 
  formatting support for hh_mm_ss (class template specialization)  |